The present invention relates to apparatus for automated actuation of a torque transmitting system and for automated shifting of a transmission in a power train of a propulsion unit of an automotive vehicle, having one or more actuators for gear shifting and for operating the torque transmitting system, and having a regulating or control unit for regulating or controlling the actuator(s) and, further, having one or more detection devices (such as one or more sensors) in signal-transmitting communication with a regulating or control unit.
Further, the invention relates to a method of operating an automated actuation of a torque transmitting system and of automated gear shifting by controlling one or more actuators for gear shifting and for operating the torque transmitting system.
Automated actuation of a torque transmitting system and of automated gear shifting serve the automation of transmissions with discrete gear ratios, and torque transmitting systems (such as clutches) in the power train. Automated shift transmissions generally are shift transmissions which can be manually shifted with a conventional linkage, but the articulation of the gear shifting can also be accomplished automatically by an actuator. Such transmissions can be so equipped that during the gear shifting process, the existing traction force is interrupted. This differs from conventional automatic transmissions in that the conventional transmissions essentially operate without interrupting the traction force during gear shifting. Conventional transmissions of this type are disclosed, e.g., in DE-OS 39 37 302 and DE-PS 35-07 565.
Compared with the conventional fully automatic automobile transmission with hydraulic torque converter and planetary gears, the automated actuation of the torque transmitting system and of the transmission, offers advantages in that the transmission can be a non-modified or slightly modified manual shift transmission. In a non-modified or slightly modified manual shift transmission, the conventional linkage for translating the shift lever movement to a manual gear shifting utilizes at least one actuator in order to automatically shift the transmission with the control unit. The actuator can be disposed within or on the outside of the transmission. Furthermore, a cylinder cam actuator, although more expensive, can also be installed within the transmission.
When gear shifting is initiated, either by a signal given by the power or by a signal given by the regulating or control unit, the torque transmitting system is at least partly disengaged by the control unit. Thereafter, the control unit causes the actuator to shift the gears or to actuate internal transmission gear shifting elements, i.e., a force generated in the actuator by the control unit moves internal transmission gear shifting elements either into active contact, or it prevents the active contact, or it causes both contact conditions to take place sequentially. The latter causes gear shifting from one gear ratio to the next gear ratio. After the gear shifting is completed, the torque transmitting system is again engaged. The actuator can be designed to provide any shifting sequence.
Generally, a synchronization device includes a synchronization ring and a coupling element and is disposed between the internal transmission gear shifting elements. These internal transmission gear shifting elements may have a toothed construction. The synchronization device provides for a rotational speed synchronization before a meshing of the individual internal gear shift elements takes place and, upon obtaining a synchronized rotational speed, it provides for an active contact through the gear meshing between the internal gear shift elements. In the majority of the gear shiftings, either done manually or by controlled actuation utilizing an actuator, the internal gear shift elements mesh without a problem. However, for a small but significant number of gear shiftings, the positioning of the gear shifting elements may be such that, e.g., top lands of the toothed constructions collide with one another during shifting, creating excessive forces. This may cause damage to the actuator or to the transmission, especially when the application of the force continues.